AD 2006-10-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Saab AB, Saab Aerosystems | SAAB 340B | Airworthiness Directives; Saab Model SAAB-Fairchild SF340A (SAAB/ SF340A) and SAAB 340B Airplanes |
| aircraft | Saab AB, Saab Aerosystems | 340A (SAAB SF340A) | Airworthiness Directives; Saab Model SAAB-Fairchild SF340A (SAAB/ SF340A) and SAAB 340B Airplanes |
Unsafe Condition
A cracked uplock axle of the main landing gear (MLG) shock strut caused by hydrogen embrittlement during the manufacturing process. This could lead to failure of the uplock mechanism, combined with a loss of hydraulic pressure, resulting in an uncommanded extension of the MLG.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the uplock axle of the MLG shock strut to determine if an affected serial number is installed. Replace any uplock axle with an affected serial number with a new one before further flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 6 months after the effective date of this AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Saab Model SAAB-Fairchild SF340A (SAAB/SF340A) and SAAB 340B airplanes, certificated in any category; serial numbers SAAB SF340A-004 through -159 inclusive, and SAAB 340B-160 through -459 inclusive.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
The FAA is adopting a new airworthiness directive (AD) for certain Saab Model SAAB-Fairchild SF340A (SAAB/SF340A) and SAAB 340B airplanes. This AD requires a one-time inspection to see if a faulty uplock axle for the shock strut of the main landing gear (MLG) is installed, and replacing the uplock axle with a new uplock axle if necessary. This AD results from a report of a cracked uplock axle caused by hydrogen embrittlement during the manufacturing process. We are issuing this AD to prevent failure of the uplock mechanism, which, combined with a loss of hydraulic pressure, could result in an uncommanded extension of the MLG.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 71, Number 92 (Friday, May 12, 2006)]
[Rules and Regulations]
[Pages 27598-27599]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 06-4309]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-24075; Directorate Identifier 2005-NM-235-AD;
Amendment 39-14589; AD 2006-10-05]
RIN 2120-AA64
Airworthiness Directives; Saab Model SAAB-Fairchild SF340A (SAAB/
SF340A) and SAAB 340B Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Saab Model SAAB-Fairchild SF340A (SAAB/SF340A) and SAAB 340B
airplanes. This AD requires a one-time inspection to see if a faulty
uplock axle for the shock strut of the main landing gear (MLG) is
installed, and replacing the uplock axle with a new uplock axle if
necessary. This AD results from a report of a cracked uplock axle
caused by hydrogen embrittlement during the manufacturing process. We
are issuing this AD to prevent failure of the uplock mechanism, which,
combined with a loss of hydraulic pressure, could result in an
uncommanded extension of the MLG.
DATES: This AD becomes effective June 16, 2006.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of June 16,
2006.
ADDRESSES: You may examine the AD docket on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a> or in person at the Docket Management Facility, U.S.
Department of Transportation, 400 Seventh Street, SW., Nassif Building,
Room PL-401, Washington, DC.
Contact Saab Aircraft AB, SAAB Aircraft Product Support, S-581.88,
Link[ouml]ping, Sweden, for service information identified in this AD.
FOR FURTHER INFORMATION CONTACT: Dan Rodina, Aerospace Engineer,
International Branch, ANM-116, Transport Airplane Directorate, FAA,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
227-2125; fax (425) 227-1149.
SUPPLEMENTARY INFORMATION:
Examining the Docket
You may examine the airworthiness directive (AD) docket on the
Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a> or in person at the Docket Management
Facility office between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The Docket Management Facility office
(telephone (800) 647-5227) is located on the plaza level of the Nassif
Building at the street address stated in the ADDRESSES section.
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to include an AD that would apply to certain Saab Model
SAAB-Fairchild SF340A (SAAB/SF340A) and SAAB 340B airplanes. That NPRM
was published in the Federal Register on March 7, 2006 (71 FR 11349).
That NPRM proposed to require a one-time inspection to see if a faulty
uplock axle for the shock strut of the main landing gear (MLG) is
installed, and replacing the uplock axle with a new uplock axle if
necessary.
Comments
We provided the public the opportunity to participate in the
development of this AD. We received no comments on the NPRM or on the
determination of the cost to the public.
Conclusion
We have carefully reviewed the available data and determined that
air safety and the public interest require adopting the AD as proposed.
Costs of Compliance
This AD will affect about 248 airplanes of U.S. registry. The
required inspection will take about 1 work hour per airplane, at an
average labor rate of $65 per work hour. Based on these figures, the
estimated cost of the AD for U.S. operators is $16,120, or $65 per
airplane.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of
[[Page 27599]]
the FAA Administrator. Subtitle VII, Aviation Programs, describes in
more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
subtitle VII, part A, subpart III, section 44701, ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.
Regulatory Findings
We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD will not have a
substantial direct effect on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866;
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979); and
(3) Will not have a significant economic impact, positive or
negative, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.
We prepared a regulatory evaluation of the estimated costs to
comply with this AD and placed it in the AD docket. See the ADDRESSES
section for a location to examine the regulatory evaluation.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
0
2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
2006-10-05 SAAB AIRCRAFT AB: Amendment 39-14589. Docket No. FAA-
2006-24075; Directorate Identifier 2005-NM-235-AD.
Effective Date
(a) This AD becomes effective June 16, 2006.
Affected ADs
(b) None.
Applicability
(c) This AD applies to SAAB Model SAAB-Fairchild SF340A (SAAB/
SF340A) and SAAB 340B airplanes, certificated in any category;
serial numbers SAAB SF340A-004 through -159 inclusive, and SAAB
340B-160 through -459 inclusive.
Unsafe Condition
(d) This AD results from a report of a cracked uplock axle of
the main landing gear (MLG) shock strut caused by hydrogen
embrittlement during the manufacturing process. We are issuing this
AD to prevent failure of the uplock mechanism, which, combined with
a loss of hydraulic pressure, could result in an uncommanded
extension of the MLG.
Compliance
(e) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Inspection To Determine Part Serial Number
(f) Within 6 months after the effective date of this AD, inspect
the uplock axle of the MLG shock strut to determine whether an
affected serial number (S/N) is installed. A review of airplane
maintenance records is acceptable in lieu of this inspection if the
S/N of the uplock axle can be conclusively determined from that
review. Do the inspection in accordance with the Accomplishment
Instructions of Saab Service Bulletin 340-32-132, dated November 3,
2005.
Note 1: The Saab service bulletin refers to APPH Service
Bulletins AIR83022-32-31, Revision 1; and AIR83064-32-11, Revision
1; both dated October 2005; as additional sources of service
information for identifying uplock axles with affected S/Ns, and
replacing the axles if necessary. The APPH service bulletins are
attached to the Saab service bulletin.
Corrective Action
(g) Before further flight after accomplishing the inspection
required by paragraph (f) of this AD: Replace with a new uplock axle
any uplock axle with an affected S/N identified by the inspection in
paragraph (f) of this AD. Do all actions in accordance with the
Accomplishment Instructions of Saab Service Bulletin 340-32-132,
dated November 3, 2005.
Parts Installation
(h) As of the effective date of this AD, no person may install
an uplock axle on any airplane if it has an affected S/N identified
in accordance with paragraph (f) of this AD.
No Reporting Requirement
(i) Although the Accomplishment Instructions of Saab Service
Bulletin 340-32-132, dated November 3, 2005, specify to send a
report with the S/N of replaced uplock axles to APPH Ltd., this AD
does not include that requirement.
Alternative Methods of Compliance (AMOCs)
(j)(1) The Manager, International Branch, ANM-116, Transport
Airplane Directorate, FAA, has the authority to approve AMOCs for
this AD, if requested in accordance with the procedures found in 14
CFR 39.19.
(2) Before using any AMOC approved in accordance with Sec.
39.19 on any airplane to which the AMOC applies, notify the
appropriate principal inspector in the FAA Flight Standards
Certificate Holding District Office.
Related Information
(k) Swedish airworthiness directive 1-199, effective November 9,
2005, also addresses the subject of this AD.
Material Incorporated by Reference
(l) You must use Saab Service Bulletin 340-32-132, dated
November 3, 2005, including the attachments listed in Table 1 of
this AD, to perform the actions that are required by this AD, unless
the AD specifies otherwise. The Director of the Federal Register
approved the incorporation by reference of this document in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Saab
Aircraft AB, SAAB Aircraft Product Support, S-581.88,
Link[ouml]ping, Sweden, for a copy of this service information. You
may review copies at the Docket Management Facility, U.S. Department
of Transportation, 400 Seventh Street, SW., Room PL-401, Nassif
Building, Washington, DC; on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>; or
at the National Archives and Records Administration (NARA). For
information on the availability of this material at the NARA, call
(202) 741-6030, or go to <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
Table 1.--APPH Service Bulletins Attached to Saab Service Bulletin
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Revision
APPH service bulletin level Date
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AIR83022-32-31....................... 1 Oct. 2005.
AIR83064-32-11....................... 1 Oct. 2005.
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Issued in Renton, Washington, on April 28, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 06-4309 Filed 5-11-06; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 4, 2026
Rights: U.S. Government Public Domain
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